I've only ever heard that term being used derogatoroly online, do you really use Aspie as a term of endearment towards your family member?

Aspie is usually not considered derogatory... more casual and friendly. Some may not like the word but it doesn't have any sort of sinister connotation. I see pretty much every synonym for Autism or Aspergers being used derogatorily online.

I've only ever seen or heard it used positively and even affectionately. If that's not usual, it's high time it be reappropriated.

My sample size of one says yes.